This is one of the most complex and hard exercise that you can do without equipment.
It requires mobility and strength from so many different muscles. From your arms to your calves. Make sure that you feel comfortable with each step and can perform 10 repetitions with good form before trying the next level.
Progressions:
This exercise can be used to build strength for future handstand or yoga pauses like the cobra later.
Warning: If you have any lower back injury: don't sit on your heels as I do in the video but stay in a tabletop position (shown at the start of the video with hips aligned with your knees) as your backward position.